GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER
Results 1 to 8 of 8
  1. #1
    Jr. Engineer
    Join Date
    Jan 2009
    Location
    Rochester, MN
    Posts
    231

    Default Aftermarket Mass Air Flow Sensors (Jet and Granatelli)

    So even though I was very skeptic about aftermarket MAFs I kept hearing a lot of good things about HP and MPG increases when using them. I bought a used Granatelli online but before I even got it I started hearing better things about the JET so I bought one of those online also. I got it from a guy on ebay who said his broke and he got a replacement one but changed his setup and couldn't use it anymore so it was never even used.

    I bought my truck just about a month ago and the only thing I had done to it was put a Hypertech programmer on it. I monitored the long term fuel trims and found that my truck was running a little lean but not too bad, an average fuel trim of about +9%. I put the Jet Maf on and could definately tell that there was a power increase with it but after a few days I noticed the check engine light had come on. It turned out that it had come on because of a lean condition, so I monitored the fuel trims and they were about +20-25% with the MAF. Today I got some MAF cleaner and cleaned the MAF as well as installed a Volant CAI with the ram air scoop and uninstalled my Hypertech so that I wouldn't have increased timing while running lean. On my way to work today the fuel trims are a little better, around +15-20% but still a lot higher than I would like. Is this a common problem with the aftermarket MAFs?

    I got the Granatelli in the mail which I have up for sale on ebay and boy oh boy did it look cheap. The Jet one looks alot better, it appears Jet removes the honeycomb and cuts some holes in the bar going across the middle for a smooth professional look. The Granatelli does not look like something I want to put in my truck, the honeycomb and the bar going across the middle are removed and the black plastic bar going across is cut down as far as possible, making the sensor wires supported by a lot less.

    Anyways, I think both of them are going on ebay, but has anybody else had problems like this? I'm sure a lot of people think they add HP and MPG which they do because your truck is running so lean but it is not the way I want my truck to run and how can they sell a product that makes your check engine light come on?

  2. #2

    Default

    Never heard of this.


    Maybe somone else has had this problem.
    Ryan

    2002 Jeep Wrangler Sport 4x4 (the Yellow Jacket)
    4inch suspension 3inch body
    Straight 6 (383 Stroker within a year)
    36inch SuperSwamper TSL.
    105,000
    Detroit Loccers
    Daily Driver Weekend Wheeler
    much more...

    2004 Sierra crew cab, 2wd, 5.3 V8
    2inch Daystar Leveling kit
    single dumped Flowmaster 40 sieries exaust(removed)
    Mb Blitz Chrome wheels
    Leer Bed Cover(for sale)
    50k miles
    :glasses:




  3. #3
    Legend

    Join Date
    Feb 2008
    Location
    Red Wing, Minnesota, United States
    Posts
    3,386

    Default

    I guess i never saw the point in a high dollar MAFS, your computer will automatically readjust the levels when it gets more air coming in the intake with a higher flowing air filter, will it not. And if the cumputer cant, a custom tune would make up for it wouldnt it, maybe i am wrong.
    99 K1500 Suburban LT "THE BEAST"
    Hypertech III, K&N, true dual
    285/75/16
    ___________________________
    Jason

  4. #4

    Default

    Quote Originally Posted by vncj96 View Post
    I guess i never saw the point in a high dollar MAFS, your computer will automatically readjust the levels when it gets more air coming in the intake with a higher flowing air filter, will it not. And if the cumputer cant, a custom tune would make up for it wouldnt it, maybe i am wrong.
    That's always been my logic. It may be wrong though, I dunno.
    Matt
    Hallsville, TX

    2005 Silverado 1500 LS Crew Cab 5.3L 2WD
    K&N FIPK II
    Magnaflow Exhaust
    Hypertech Max Energy Programmer
    Suspension Leveling Kit
    Putco Element Window Visors
    Carriage Works Billet Grille
    TruXedo TruXport Tonneau Cover


  5. #5

    Default

    Quote Originally Posted by vncj96 View Post
    I guess i never saw the point in a high dollar MAFS, your computer will automatically readjust the levels when it gets more air coming in the intake with a higher flowing air filter, will it not. And if the cumputer cant, a custom tune would make up for it wouldnt it, maybe i am wrong.
    Yea I agree with you. There is no point in selling your Jet MAF. All you need done is a custom tune and they will notice its running lean and compensate for it. Plus you will get added hp and mpg so why not spend the few hundred?

    Cody - AR
    2003 GMC Sierra 2wd
    275/70/16 Toyo Proxes S/T
    Hypertech Max Energy Programmer
    Bomz Intake
    Kicker ZX750 amp powering 2 CVR 12" subs

  6. #6
    Jr. Engineer
    Join Date
    Jan 2009
    Location
    Rochester, MN
    Posts
    231

    Default

    The computer will make up for the added fuel, but only to a point. That point is 25%. So if my LTFT's are at 25%, that means they really should be higher and whatever that difference is is how lean it is running. I suppose a custom tune with it would probably be the way to go but that's too expensive. I just bought a DiabloSport Predator, I can adjust my fueling with that right? Or will that only do WOT fueling? My last car was a modified Grand Prix GTP and I had custom tuning software for it and I really liked that but it only cost me about $350 and it was very neccessary due to the mods that I had done where everything I've seen for my truck would be at least $500 and I don't really plan on doing anything that will neccessitate (Is that a word?) that.

  7. #7
    Legend

    Join Date
    Feb 2008
    Location
    Red Wing, Minnesota, United States
    Posts
    3,386

    Default

    nelsonperormance is 275 i think or try blackbearperformance.com his nale has been popping up on here alot lately and is very cheap

  8. #8

    Default

    The granatelli are junk. Had it and return it. The unscreen gives a little better pick up preformance off a light but lost some parking lot driving.

    I upgraded with a 85mm MAF, then rescaled to with my HP Tuners program.
    Last edited by TrailLeadr; 09-08-2011 at 10:10 AM. Reason: Removed Spam links

Similar Threads

  1. Mass Air Flow Sensor Problems
    By chevyman1297 in forum General Chevy & GM Tech Questions
    Replies: 7
    Last: 09-25-2009, 07:10 PM
  2. Mass Air Flow
    By Coptalker in forum Chevy Silverado Forum (GMC Sierra)
    Replies: 1
    Last: 08-03-2009, 07:08 AM
  3. Aftermarket Air Flow Sensors and Descreening
    By JennaBear in forum Performance & Fuel
    Replies: 6
    Last: 06-22-2009, 09:46 PM
  4. High Flow Mass Air Sensors
    By b5davis in forum Performance & Fuel
    Replies: 2
    Last: 04-29-2008, 05:19 PM
  5. Mass Air Flow Sensor
    By andrejj in forum Chevy Colorado Forum (GMC Canyon)
    Replies: 1
    Last: 09-13-2006, 02:34 PM

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •